There are many industries and applications where it is useful to gather data generated by multiple sources and process and correlate that data in real-time. Examples include manufacturing process monitoring and control, web analytics (e.g. clickstream analysis), financial services, power utilities, healthcare and IT monitoring. The analysis of the data which is generated by multiple sources may be performed by a complex event processing (CEP) server which receives streams of data from the various sources and implements standing queries on the data received. The CEP server may then output data to event monitoring devices (e.g. to alert someone of an error or fault situation), data stores or to devices running applications which display results of the real-time analysis (e.g. key performance indicator dashboards or trading stations).
The embodiments described below are not limited to implementations which solve any or all of the disadvantages of known distributed analytics systems.